crowley



- l; P. CROWLEY. METHOD OF AND APPARATUS FOR DRAWING CONTINUOUS SHEETS OF GLASS. APPLICATION FILE-D MAR. 15. m1.

1 328, 268. 1 Patented Jan. 20. 1920.

2 SHEETS SHEEI I.

72 We j g j f.

1. P. CROWLEY. METHOD OF AND APPARATUS FOR DRAWING CONTINUOUS SHEETS 0F GLASS. APPLICATION FILED MAR. I5, 19!]- 1 ,328, 268, Patented Jan. 20, 1920.

2 SHEETS-SHEEI 2.

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UNITED STATES PATENT OFFICE.

JOSEPH P. CROWLEY, OF TOLEDO, OHIO, ASSIGNOR TO THE LIBBEY-OWENS SHEET GLASS COMPANY, OF CHARLESTON. WEST VIRGINIA, A CORPORATION OF OHIO.

METHOD OF AND APPARATUS FOR DRAWING CONTINUOUS SHEETS OF GLASS.

Specification of Letters Patent.

Patented Jan. 20, 1920.

Application filed March 15, 1917. Serial No. 135.801.

To all whom it may concern Be it known that I, JOSEPH P. CnowLEY, a citizen of the United States, residing at Toledo, in the county of Lucas and State of Ohio, have invented certain new and useful Improvements in the Methods of and Apparatus for Drawing Continuous Sheets of Glass, of which the following is a specification.

My invention relates to certain new and useful improvements in methods of and apparatus for drawing continuous sheets of.

glass; To my knowledge continuous sheet glass is now commercially made by but one rocess, and that is covered by Patent Namiers 876,267, 966,652, 966,653. 973,002 and 1,160,692. In such process the glass is drawn vertically and bent over a roll to a horizontal positlon. The glass as it passes over the roll is comparatively soft and plastic, with only a very thin surface glaze so that it takes the impression of the roll surface and is always more or less marred thereby.

The primary object of my invention is to avoid bending of the sheet, to thereby eliminate roll impressions and produce the best possible grade of sheet glass mechanically. and at the same time permit the speed of drawing to be increased.

Other objects of the invention and the exact nature thereof will appear hereinaften.

An embodiment of my invention is illustrated in the accompanying drawings wherein:

Figure 1 is a longitudinal section through the working end of the tank. pot, roll and drawing apparatus. Fig. :2 is a transverse section through the pot and roll. Fig. 3 is a side eleiation showing; one of many drives that can be employed to rotate the roll.

Referring to Fig. 1, the molten glass 1 is prepared in the customary way in the meltmg tank and flows from the working end 2 of the tank into an adjoining pot or drawing chamber 7. 'lhctemperature of the glass in the pot is reigu'ilated by a heating chamber 8 beneath thepot. A glass gathering roll 4,- prefcrably made of clay, but which can he of any suitable material, is mounted on a shaft 5. preferably non-circular in cross-section for driving the roll. My invention is not limited to this construction of ml], as I could use a roll made in one piece without a shaft. or the roll could he made in sections mounted on the .sha ft. The

present invention comprehends the use of any roll adapted to the process herein set forth, regardless of its construction. Above the roll 4 is a fire or Wind box 6. The mechanism for drawing a sheeuof glass comprises the knurled rolls 9, carrier rolls 10,

draw table 11 and clam bars 12, this form of drawing mechanism )eing shown in the Patents 867,948 and 876,267 hereinbefore mentioned. i

The roll 4 dips into the molten glass 1 and is continuously rotated in the direction in withdrawn so that the glass draws in a sheet from the pool, the point of sheet formation 16 shifting upward on the roll 4. The glass is thus supplied directl from the layer of molten lass 3 on the ro l which rotates continuous y. The bait is drawn over the carrier rolls. 10 by means of. the draw table 11 and clamp bars 12, and the sheet of lass 13 thus started is drawn continuously y said draw table and clamp bars.

It will be seen that the roll 4 provides a gatherin and transfer device by which the molten gd'ass is continuously gathered from the pool and transferred-or lifted to the drawing point 16, which forms the base bf the sheet. The glass is carried upward with the roll faster than it is formed into the sheet, so that a portion of the glass adhering to the roll is carried beyond the sheet aroun the roll and back to the pool. It will be noted that there is a continuous flow or movement of the glass in an upward and forward direction to the under surface of the sheet 13 and an upwardand rearward movement of glass away from the upper surface of the sheet at the base 16. Owing to the viscosity and tenacity of the glass the force of gravity is counteracted so that the The height of the drawing point or base 16 of the sheet above thelevel of the molten lass 1 is governed by a number of factors, ncluding the speed of the reel 4, the depth. to which it is immersed, the s eed of draw-' the temperature of the,

pass 3 on the and the temperature 0 hi 10% the glass fh *the pot 7. Anyone or more of these factors may be .varied to regulate said drawing point: 1

I show auvanable "is (1 motor 1 draw table 11 and clamp bars 12. The temperature of the glass on the gather-in roll may be regulated by means pf the re or Wind box 6, and the temper 'ture of the glass 1 in the pot may be regul iiaed by means of the fire in chamber 8.

vof the glass 1.

The roll 4 constantly replenishes the supply at the source of drawing as the drawing proceeds. This supply can be increased or decreased by changing the speed of the roll, the depth of dip ing and the temperature he supply at the source of drawing can thus be regulated to meet the requirements of the sheet 13. Although I have'described and shown the roll dipping in the glass in the pot 7 and have also shown the sheet being drawn horizontally from the drawi point 16, it will be understood that the r0 could be dipped in molten glass contained in any receptacle; for example, it could be operated in the working end 2 oi the melting tank. The pot construction wn is favored because it has proved suc- "cy #flll in the process set forth in the coy .iding application of I. W. Colburn, Serial Number 70,927, and has the means for adjusting the temperature of the glass in the Spot. Also the sheet 13 can be drawn in any gpractical direction from the roll.

. Variations may be resorted to within the spirit and SUOPBOiEIIY invention. The princlples of my invenion"'mayleeapplied in drawing glass otherwise than in shpet form "or in a continuous dileet.

What I claim is: r

1. In an apparatus for drawing a conthe combination with meansto supply a p 01 of molten glass, of a' gathering roll partly immersed in the molten glass, means for rotating the roll and thereby gathering molten glass on the roll and transferring it to a drawing point, and means to draw the glass in a sheet from said roll in a direction normal to the roll at said drawing point.

s e to the rollend can t ereby regulatethe;

QQAn apparatus for forming a continufor molten glass, a rotating roll partly immersed in the glass, and means to draw the glass in a sheetfrom the roll in a direction normal thereto.

In an apparatus for forming a coni-lIll lOllS sheet of glass, the combination of a. container for molten glass, a lifting dewice for lifting a portion of the glass to a drawing point, means to draw glass in a sheet from ti a lifting device at said drawing point in a direction perpendicular to the surface of the lifting device at the drawing point, means for heating the glass on]t1ie lifting deviceymeans for operating ithe, lifting device, means for raising and lowering the lifting device, and means for regulating the speed of lifting.

4. In an apparatus for drawing a continuous sheet of glass, the combination of a glass gathering roll rotating in position 'to gather glass from a molten mass, means for regulating the amount of glass gathered by the oll, means for regulating the temperature of the gathered glass, and means for drawing the glass in a sheet from the upwardly moving surface of the roll and maintaining the drawing point at the roll above the level of said mass, said roll being the sole means for lifting the glass from the mass to said drawing point.

5. In an apparatus for drawing a continuous sheet of glass from a molten mass, the combination of means for heating the mass, a roll partly immersed in the mass, means for rotating the roll whereby glass is gathered thereon, means for regulating the amount of glass gathered on the roll, means for regulating the temperature of the glass on the roll. and means for maintaining a drawing point on the roll and drawing a continuous sheet of glass from the roll at said point in a direction perpendicular to the surface of the roll at said point, the width of the sheet being approximately the length of the roll.

6. The method of drawing a continuous sheet of glass, which consists in causing a surface to move upward from a mass of moltcn glass and carry glass upward therewith, and drawing glass laterally from a drawing point at said surface above the level of said muss while a portion of the glass carried ipu'm-d with said surface beyond the drawupper face of the sheet and toward the under face of the sheet.

8. The method of drawing a. continuous sheet of glass, which Consists U1 transferring glass from a molten mass to a drawing point by a continuously moving surface to which the glass adheres, drawing glass laterally in a continuous sheet from said drawing point, and movie a portion of the surface of the trz'msferrcll glass away from the upper face of the sheet as the drawing proceeds. while molten glass is supplied to the under face of the sheet.

9, The method which consists in ccimtinuously drawing a sheet of glass laterally, continuously and mecl\anicall gatherin the glass from a molten iii-ass, and causing continuous inm-enmnt of glass upward and to ward the under face of the sheet and upward and away from. the upper face of hc sheet, the upwardly moving having .in uncon fined surface merging into the under surface of said sl'ieet.

id The method which. consi in -,:r' utiim ousl drawing a sheet of glass liorixontaliy, lnec anical-ly moving glass upuard from a pool of to the drawing point, and causing a continuous movement of glass away from the upper face of the sheet hack into the pool adjacent the poi nt at which it is Withdrawn from the pool.

- 1].. A paratus for forming a continuous sheet 0 glass, comprising a receptacle for molten glass, a rotating roll partly immersed in the moltenglass, and mea e to draw the glass horizontally in a sheet from an upwardly moving portion of the roll surface.

12. The combination of means providing an upwardly movingsurlocc of molten or plastic glass, and means to draw glass horizontally in a sheet from said surface, said surf ce being unconfined below and above the drawing point.

13. The coinoination of HT us. prm'iding an upwmdl v moving exposed surface oi molten and. means to draw glass lat-en ally from said surface at an intermediate point tllfb'lfii 14. The wnhination of means for (:on'i'im uously-drawing a sheet of glass horizontall and means to maintain a continuous supp y of molten glass moving vertically at the base of the sheet. said means comprising a rotat ing roll partly immersed in a. pool of glass.

15. In sheet glass forming apparatus, the combination of a gathering device having an upwardly moving surface, means to supply molten glass to said surface for upward movement therewith in a continuous sheet, and means to draw glass horizontally in a contis'iuculs sheet from said surface as it moves upward.

1d, The combination of means to carry molten glass upward in, a continuous sheet from a pool, one surface of the sheet being iutmonlim-d and means to draw glass in a sin-ct from said surface at an intermediate point thereof.

17. The method which consists in providing an upwardly mo ing surface, causing a sheet of glass to move upwardly on said surface from a pool of molten glass, and drawing a portion of said glass laterally while sizolhcr PIIII'tlQTl ontinues its upward movement beyond the drawing point.

18. The method which consists in causing giass to move upwardly in a continuous sheet from a'pool of molten glass, continuously drawing a portion of said sheet transversely, and. returning the remaining portion to the pool, said sheet havin an exposed and unconfined surface exten ing from the pool to the drawing point.

19, The method which consists in causing last to move upwardly in a continuous sheet l 'om a pool oi molten glass, deflecting a portion of said upwardly moving glass to a horizontal direction and drawing it in a continuous sheet, andretaining the remaining portion to the pool, the u Wardly moving glass presenting an uncon. ned surface extending from the pool upward to and merging nto the under surface of the horizontal sheet.

Signed at Toledo, Ohio, this tenth day of March, 1917.

JOSEPH P. CROWLEY] 

